Determining a similarity between objects may be useful in many contexts. For example, a determined similarity between objects may be useful to recommend documents or products, to suggest content such as news articles, music, movies, web pages, images, and the like, to compare various sets of data, and so on.
In determining similarity between objects, some conventional techniques employ a hierarchical domain structure that is used to represent the objects. However, the hierarchical domain structure may be utilized in such a way that a measure of similarity determined using these techniques inaccurately reflects the actual similarity between the objects, thus causing these techniques to fail for their intended purpose.